Use the included BASIC program "DBWRITE" to rewrite the desired
      sector(s) with a new data block ID (creating the 22 Error).
      "DBREAD" can then be used to read the protected sector(s) and
      place it in drive memory at $0300 where it can be accessed with a
      "Memory-Read" command. From there you can either transfer the code
      down to the computer or leave it in the driveg if it's drive code.
      You may use the included assembly code in a machine language
      program if you wish.
      
      DBWRITE.ASM
      
        This program is for educational and personal use only
        No commercial use of this program is permitted.
        All rights reserved  (C) 1989 K.J.P.B.
      
      ***********************************************************;
      Job:
        Rewrite a data block with a different
        data block ID code. High nibble of code
        must be $0x, $1x, $4x, $5x, $8x or $Cx;
        (x = any hex number from $0 - $F)
        The following code must be written to
        drive memory $0500 and can be executed
        from BASIC with the following statement:
      
        OPEN 15,8,15,"UC:"+CHR$(new id code)+CHR$(trk)+CHR$(sec)
        CLOSE 15
      ***********************************************************;
      
         org   $0500    ;code executes in drive here writdbid
         sei            ;disable interrupts
         lda  $47       ;save current data block id char
         sta  oldid
         ida  $203      ;get new id from command buffer
         sta  newid
         lda  $204      ;get track for new data block id
         sta  $06       ;will be read into $0300
         lda  $205      ;get sector for new data block id
         sta  $07
         ida  #$B0      ;seek track/sector
         jsr  waitjob
         ida  #$80      ;read track/sector into $0300
         jsr  waitjob
         lda  newid     ;setup new data block id
         sta  $47
         ida  #$90      ;write trise with new data block id
         jsr  waitjob
         pha            ;save error code ($01 = O.K.)
         lda  oldid     ;restore old data block id
      
            K.J. REVEALED TRILOGY    PAGE [142]    (C)1990 K.J.P.B.